Bill Amend put his physics degree from Amherst College in Massachusetts to good use. His syndicated comic strip, FoxTrot, is filled with science and math references, including the occasional equation that can actually be solved.

Amend, who grew up in Burlingame, was inspired by his own large family when he invented the Foxes: parents Roger and Andy, teens Paige and Peter, and geeky youngest son, Jason. First published in 1988, the strip was a quick success.

Amend, 48, scaled back to writing FoxTrot on Sundays only in late 2006 and won a National Cartoonists Society Reuben Award for outstanding cartoonist of the year in 2007. He recently released "The Best of FoxTrot," a two-volume anthology covering the first two decades of the strip. We got in touch with him at his Kansas City, Mo., home.

Q:Looking back 20 years, have your sympathies shifted from the FoxTrot children to the parents?

A: Yeah, definitely. The biggest change over the course of the strip's run is I now have two teenagers of my own who seem to think it's funny to throw various FoxTrot misbehaviors back in Dad's face. In hindsight, I should've written a comic about angels or something.

Q:What was the most enjoyable part about looking back at 20 years of strips?

A: Finding strips and storylines that I'd completely forgotten about. Some I'd probably forgotten on purpose, but some I really liked.

Q:What made you cringe the most?

A: My art style went through a phase somewhere around years three to six where everyone looks really squat. I must've thought it looked good at the time, but they kill me a little to look at now. Like old photos with ruffled tuxedos.

Q:You include a lot of math puzzles and science references in your strips. Have you ever made a mistake?

A: Oh, yes. And how the e-mails flow on those days. I probably make no more math mistakes than I do spelling ones, but my syndicate editors can catch the spelling errors before the strips go out. The math they leave mostly up to me. My favorite e-mails are the ones pointing out some math mistake where there wasn't one, so I get to turn the tables and explain how they were wrong.

Q:Has your life changed for the better since you decided to make FoxTrot a Sunday-only strip?

A: Yeah, it's infinitely more sane now. Nineteen years of all-nighters and skipped meals was about my limit. I still stress out when the deadline nears, but it's not a perpetual sense of stress, which is how it was for so long.

Q:Other cartoonists hire more artists and keep running their strip daily. What stopped you from doing that?

A: I've always treated FoxTrot as my personal little creation, and I'd hate to muddy that up by bringing in other people at this point. I like that the Sundays are still pure me, while done at a pace that isn't going to kill me.

Q:Where do you keep your Reuben Award?

A: It's on a shelf in my studio next to a toy AT-ST I bought back when "Return of the Jedi" came out.

Q:What Bay Area restaurant, business or other institution are you most excited to see when you come back to visit?

A: Sam's Sandwiches in Burlingame is a required stop for me, even though the last time I was there they had a zillion Get Fuzzy strips taped up and zero FoxTrots. And I usually try to get at least one burrito in Redwood City. The Midwest has lousy burritos.

A: One night a couple months ago I drank too much and started sending Facebook friend requests to various "Glee" cast members, and Dianna actually accepted mine, so she obviously thinks I'm super awesome and would enjoy my lunch company. Either that, or she accepts everyone's friend request and at lunch would say "Bill who???" and crush my ego to dust. Hmm. This is a tough decision.

Q:Please tell us something on the record that people don't know about Pearls Before Swine cartoonist (and Santa Rosa resident) Stephan Pastis.

A: He writes his strips using a Ouija board. The real author of Pearls Before Swine is a dead Civil War-era seamstress named Lucianne Candy fish. Apparently, Bil Keane's great-great-great-great grandfather used to tease her in school, so all the strip's mockery of Family Circus is payback.